Self-sealing coke oven door



Dec. 28, 1954 E. WQLFF 2,698,289

SELF-SEALING COKE OVEN DOOR Filed April 18, .1952 2 Sheets-Sheet l INVENTOR ERNST NOLF'F ATTO R N EY Dec. 28, 1954 Y wo 2,698,289

SELF-SEALING COKE OVEN DOOR Filed April 18, 1952 2 Sheets-Sheet 2 INVENTOR ERNST NOLFF BY & M ATTORNEY United States Patent SELF-SEALING COKE OVEN DOOR Ernst Wolff, Bochum- Linden, Germany Application April 18, 1952, Serial No. 283,047

4 Claims. (Cl. 202-248) The present invention relates to, and discloses and claims lmprovements on prior metallic self-sealing coke oven doors of well known type, and discloses and claims a novel method of sealing the joint between a coke oven door and the door way closed by said door. The present appllcation is a continuation in part of my prior application, Serial No. 126,316, filed November 9, 1949, and now abandoned.

Metallic self-sealing doors for coke ovens and the like, proposed and used prior to the invention which I disclose and claim herein, are commonly of a type including a sealing frame mounted on the body of a coke oven door in such manner as to be bodily movable relative to said body toward and away from the associated door.

Each such sealing frame is adjustable relative to the corresponding door body and is adapted to be secured in its different ad ustment positions by a multiplicity of presser bolts mounted on the door body for adjustment in the direction of movement of the sealing frame. Said bolts are spaced along the perimeter of the door body.

As a door of the known type described is being secured in its closed position by tightening its conventional latch screws, pressure is transmitted to the sealing frame by the presser bolts. Should leakage occur between the sealing frame and the door frame, the sealing frame is moved closer to and pressed against the door frame by tightening the said presser bolts. A main cause of such leakage is the distortion of the door frame which is caused by the heat of the oven and the consequent distortion of the seating or sealing face of the door frame. Incrustations on the seating face of the door frame may be caused by tar residues and as a result, the tightness of the fit of the sealing frame on the door frame seating face may often be adversely affected.

When upon such an occurrence, an attempt be made to make the sealing frame fit against the uneven seating surface of the door frame by tightening or loosening the presser bolts, these bolts must distort the sealing frame and as such distortion is chiefly made possible by the inherent resilience of the sealing frame, this frame usually assumes its undistorted form when the door is opened. Therefore, when the door is again closed, the sealing frame must again be distorted. Moreover, the sealing frame is exposed to the influence of the oven heat and suffers permanent bending deflections which must be corrected by adjusting the presser bolts. The above mentioned distortion of the sealing frame is in effect, a reformation of that frame. Consequently, it is often not feasible to stop leaks by adjusting the presser bolts and although those bolts may be provided in comparatively large numbers, the necessary spacing between the bolts is still large enough to make it diflicult, if not impossible, to deform the sealing frame in the requisite manner.

In the use of the known construction, oven operators increasingly tighten the presser bolts in the mistaken belief that such tightening will eventually produce a tight seal. However, when incrustations appear on the door frame, they cannot be eliminated by merely increasing the force exerted by the presser bolts, even though the bolts be tightened to their fullest extent. Such force increase merely locally compresses the incrustations and gives rise to a further great difliculty, since while a skilled man may tighten the presser bolts with care and sensitivity, coke oven operators are usually unskilled men and they generally so tighten the presser bolts that the strength of the structural members of the closure is exceeded. When the presser bolts are thus tightened, the

2,698,289 Patented Dec. 28, 1954 counter-forces which are created are transmitted via the body of the door to the door locking devices. Thus the tightening of the presser bolts often causes the door body, and particularly the door locking devices, to suffer permanent deformation.

Again, as a presser bolt maintains its position once it has been tightened, the counter-forces which are produced in the door body and the locking devices by such tightening persist during the corresponding coking period, and when the door is to be opened, the movable spindles of the locking devices must be actuated under the full effect of these forces, so that premature wear of these operating parts occurs. In consequence of the repeated subjection of the door frame and the sealing frame to the heat of the oven together with the permanent deformations which are created as described above when the sealing frame is pressed to the sealing face of the door frame by resiliently bending, the difliculties in the way of obtaining a tight seal progressively increase, and make necessary continuous readjustment of the sealing frame, with its attendant disadvantages and loss of time.

The general object of the present invention is to provide a self-sealing coke oven door with novel sealing provisions whereby the above mentioned disadvantages are avoided or substantially reduced.

A primary object of the invention is to provide a coke oven door with sealing means including a sealing member in the form of a continuous belt or strip of flexible sheet metal surrounding the outer metallic body portion of the door, and having its inner edge in engagement with, and having its flat sides transverse to, and outwardlyfacing, sealing surface of a metallic door frame surrounding the end of a coking chamber, and so disposed that said inner edge may be forced into contact with said sealing surface by the application to the outer edge of the sealing member of a hammer blow or blows, or impact force or forces. ,As used herein and in the appended claims, the term impact force means a force produced by the weight and impact velocity of an impacting body.

A more specific object of the invention is to provide clamping means for normally holding the inner flat side of said sealing member in stationary frictional contact with a door surface transverse to said seating surface when the door is in its normal closed position, except when an adequately large impact or shock force is being applied to the outer edge of the sealing member.

A further object of'the invention is to adapt an existing door, initially constructed with a sealing rim frame including a flexible sealing element transverse to the door frame sealing surface, and bolts or analogous elements mounted on the door body for pressing said element into sealing contact with said seating surface, for operation in accordance with the present invention.

In such adaptation of an existing door, I advantageously replace its original flexible sealing rim frame by a rigid frame, which may be formed of cast iron and includes a flange which I rigidly connect to the door body to form an extension of the latter which supports and frictionally holds a sealing member adjustable relative to the door frame seating surface in accordance with the present invention.

In the preferred form of the invention, screws or bolts form tightening means which are adapted to press the sealing member against the door body, and which are adjustable to vary the frictional resistance to movement of the member on the door body.

The invention can be embodied in a construction in which the frictional resistance to movement of the sealing member on the door body is such as to absorb the counterpressures which occur at each point of sealing contact of the sealing member with the door frame sealing surface, and also absorb the counter-pressures which may arise due to elastic bending of the sealing member. Consequently, the invention renders it unnecessary toemploy presser bolts which exert pressure in the direction of movement of the sealing member, that is in the line of the counter-pressures.

Adjustment of the sealing member when required to close local leak paths, is effected by hammer blows or impact force applications which temporarily overcome the frictional resistance to movement on the door body of the particular portion of the sealing frame to which the force is applied, and permit the frictional resistanceto quickly become fully effective again.

The blows may be delivered directly to the outer edge of the sealing==member, and as movement of the sealing member only takes place under a blow, no counterpressures are'created which act on the door body and the latching-device. On the contrary, at the instant at which the sealing member receives a hammer blowthe door body tends-to move towards the oven, thus easing the pressure on'the latchingdevice; Suchtendeney-to movement of the door body depends, of'course, on the amount of friction=between the-seali'ngframe and the door body. As soon as the blow ceases, the'frictional resistance to movement of the. sealing'frame'relative to the door body again becomes effective to hold the sealing frame in fixedposition on the door body so that the counter-pressure that can be transmittedis governed'by the frictional resistance to said movement and corresponds to the pressure with which the sealing frame must be held against the door frame to achieve sealing plus the force which corresponds to such elasticbending deformation-as may'be required. Even should unnecessary blows be imparted to the sealing frame after this frame has made sealing contact with the door-frame, no suchdistortion of the sealing frame, and no such overstraining of the parts of the latching device can occur as may result from the employment of the known presser bolts. This results from the fact that each blow on the sealing frame is transmitted through the sealing frame directly to the door frame without creating any undesirable counter-pressure.

Furthermore, adjustment of..the sealing frame by means of hammer blows provides the additional advantage that if, for example, the edge of the sealing frame hits encrustations formed on the seating face of the door frame, these encrustations can be chipped off by the blow owing to the edge-of the sealing frame acting as a chisel, this etfectdiifering from that produced by a pressure bolt which can only move forward gradually. as it is turned.

The invention has the further considerable advantage that since the blows required to adjust the sealing frame maybe imparted to portions of thecframeas. close to one another asis. desired, a better fitting of the sealing frame on the door'frame can be achieved than is possible with the prior: presser bolts. Those bolts arenecessarily spaced a substantial distance apart. Theinvention thus makes it possible to makean effective adjustment of the precise portion ofthe-sealing framewhich permits aleak to occur.

The various features of novelty which characterize my invention: are-pointed'out with particularity in the claims annexed to andforminga part of this specification. For -a better understanding; of the. invention, however, its advantages. and specific. objeetsattained with its use,

reference should be had tothe accompanyingdrawings and escriptivematter'in: which I haveillustrated and described preferred embodiment of the invention.

Of the-drawings:

Fig. l is a crosssection through a door in place in an oven:

Fig. 2 is anelevation.illustrating:a detail of construction;

Fig. 3 is a horizontal section of a' portion of the door shown in- Fig. 4, and. illustrates the adaptation of a door of a type known to the prior art for .use in accordance with the present invention;.and

Fig. 4 is an'elevation of a portion. of the door shown in Fig. 3.

Referring first to the construction shown in Figs. 1 and 2, a door frame 11, whichv receives a door 12, is fixed in the coke oven brickwork 10. The frame 11 is continuous, i. e. without gaps in its perimeter structure, and surrounds the rnouth .of the corresponding coking chamber which extends from one side to the other of the coke oven battery. The door 12 comprises a body 13 which is made of cast or wrought iron, the front face of the body 13 being directed towards the oven and provided with the usual refractory pador plug 15, this pad being retained imposition by means of clamps 14 and entering the door opening after the manner of'a stopper.

The door-body 13 is provided witha seating face or bearing surface 16 which is:transverse to the side of the battery and extends continuously around the entire perimeter of the body 13. .Asealing member or frame 17, which is also continuous i. e. .unbroken, frictionally 4. engages the face 16. The frame 17 is formed of flat steel strip, the-inner broad side of-which closelyengages -the face 16. in the form shown, the sealing member 17 is in effect an endless sheet metal belt surrounding and fitting snugly against the bearing surface 16. The frame 17 is provided with horizontal slots 18 which are spaced along the perimeter of the frame, and through these slots threaded clamping members in .the form or stud bolts or screws 19 pro ect in a direction normal to the direction of adjustment of the frame 17 on the body 13. As shown, nuts 20 threaded on the members 19 bear on the outside broad face of the sealing frame 17 through interposed washers, .and press the frame tightly against theface 16, thus increasing the fractional resistance to movement of the frame 17 on the body 13. When required, additional frictional resistance to movement between the sealing frame 17 and the seating surface 16 may be introduced by interposing additional relatively slidable members between the relatively movable members, the washers on the screws 19, the nuts 20, the sealing frame 17:and-the door body 13. A layer of asbestos 21 is arranged between the door body 13 and the clamps 14 which retain the pad 15', with the outer edgeof this layer abutting against the inner surface of the frame 17 so that, in conjunction with the close fitting of the frame on the seating face 16, gas is prevented from escaping at this place.

After the door 12 is inserted in the door-frame 11, the locking latches 22 are swung into engagement with the hooks 23 which are fixedly mounted on the-outer portions of the frame 11, and the door is then moved bodily in the direction of the oven interior by turning the screw threaded spindles 24 until the chisel like leading edge-25 of the sealing frame 17 bears on the seating face 26 of the door-frame 11. If, now, leaks appear at any spot, for instance as a result of Warping of the door-frame 11, and/ or warping of the sealing frame 17, or by reason of encrustations deposited on the seating face 26, the sealing frame 17 may be driven'into joint sealing engagement with the face 26 byhammer'blows on the outer edge of the sealing frame. Each such blow temporarily evercomes the frictional resistance to movement of the frame 17 and relative to the face 16 and the nuts 20, but this frictional resistance again takes full effect immediately after a blow is made, so that the sealing frame is retained in the position to which it has been moved'by the blow. As the force of the blows is exerted directly on to the sealing frame 17 no counter-pressures which couldjleadto deformation of the door-body 13 or the members of the locking device 22, 23 and 24 can arise.

Figs. 3 and 4 illustrate the adaptation of the present invention to a coke oven door structure of an old and widely used type, one form of which is shown in U. S. Fatent 1,908,501 of May 9, 1933. To convert an existing door of the general type illustrated inv said prior patent into the door embodying the present invention shown in Figs. 3 and 4, the sealing means parts of the door shown in said, prior patent are removed, and a rigidv frame 40 is attached to a door body like the door-body 13a shown in Figs. 3 and 4. The door body. 13a. is substantially similar to the door body shownin said prior patent except in respect to the sealing means attached to the door body part 13b shown in Figs. 3 and 4. The frame 40 shown in Figs. 3 and, 4, is attached to the door body 13a by screws or studs 41. The latter clamp a flange portion 42 of the frame 40 against the outer side of the fiange.3l. The latter clamp a flange portion 42 of the frame 40 against the outer side of the flange 31. The frame 40.may be a metal casting and includes an outwardly extending flange 43 formed with a machined outer face 16a which extends in the direction-of the longitudinal axis of .the oven. A sealing member 17a which may 'be like the member 17 previously described, is pressed into frictional engagement with the face 16a by parts like the studs 19 and nuts 20, shown in Figs. 1, 2 and 3. As shown in Figs. 3 and 4, however, the sealing member 17a is pressed into frictional engagement with the face 16a of the frame 40 by hook numbers 44. Each hoole -44 includes a claw portion which engages the outer side of the frame or sealing member 17a and includes a shank portion 45 which extends through the flange 43 of the frame 40. The end of each shank is threaded for engagement with a clamping nut 46 which bears against :the inner side of the flange 43. The shankportions 45. areat the outer side of, and are normally spacedaway-fronr the outer edge of thesealing frame 17a. A packing strip 47 is interposed between the frame 40 and the door body flange 31, to, prevent gases from escaping through the joint between the frame 40 and the door body 13a.

As will be readily understood existing doors which differ in form from the door shown in Patent 1,908,501, may be converted into doors constructed and operating in accordance with the present invention. In their converted form, such doors may include frame members differing in shape from the frame 40. In general, how

ever, each such frame must be provided with a sealing surface corresponding to the surface 16a, for frictional engagement by a suitable sealing member like or corresponding to the member 17a, in that it is adapted to have its inner edge pressed into continuous contact with the door frame sealing surface 26 by force, such as hammer blows, applied whenever and wherever needed to eliminate leakage space between the outer edge of the sealing member 17a and the immediately adjacent portion of the door frame sealing surface 26. As will be readily understood, the conversion of existing doors into doors adapted for use in accordance with the present invention is relatively simple, and the converted doors may be readily cleaned when necessary.

The application of a hammer blow to the outer edge of the sealing member 17 of Fig. 1 or 17a of Fig. 3, subjects the sealing member to an impact or shock force which depends on both the weight and the velocity of the hammer. That impact force is similar in character to the force applied to the upper end of a pile by the falling weight of an ordinary pile driver. A hammer blow force is thus radically different in character from the slowly applied force produced by the rotation of a tightening screw like the screws 33 shown in Fig. 5.

While in accordance with the provisions of the statutes, we have illustrated and described the best form of embodiment of our invention now known to us, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of our invention as set forth in the appended claims and that in some cases certain features of our invention may be used to advantage without a corresponding use of other features.

Having now described my invention, What I claim as new and desire to secure by Letters Patents, is:

1. In maintaining a gas tight seal between an outer metallic door-body portion of a coke oven door and the outwardly facing sealing surface of a metallic coke oven door-frame surrounding a door-way into which an inner portion of said door normally extends, by the use of a sealing member in the form of a continuous band of strip metal supported by said door body and having fiat inner and outer sides transverse to said sealing surface and having an inner sealing edge normally in engagement with said sealing surface, and having said inner side in contact with an abutting bearing surface of said metallic door body portion, the method which consists in applying force to the outer side of said band to normally hold the inner side of said band in fixed frictional engagement with said hearing surface to thereby prevent sliding movement of said band relative to said abutting surface, and applying to the outer edge of said sealing member at a point along the length of the said outer edge which is displaced from said sealing surface by a distance greater than the distance between said point and the inner edge of the sealing member a distorting force produced by the weight and impact velocity of a body impacting against said outer edge, said sealing member being normally held in sealing engagement with said sealing surface substantially entirely by the frictional contact between the inner side of said sealing member and the adjacent surface of the door.

2. Self-sealing door means for use in closing a door opening at the end of a horizontal coke oven chamber having a door frame with an outwardly facing sealing surface at the margin of said opening, comprising in combination, a metallic door-body formed with a peripheral bearing surface which is transverse to said sealing surface when the door is in position to close said door opening, a sealing member in the form of a continuous flexible metal strip surrounding, and having a flat inner side in engagement with said bearing surface, clamping means carried by said door body and acting between the latter and the fiat outer side of said sealing member to normally hold the latter in frictional engagement with said bearing surface, said sealing member having an inner edge in abutting relation with said sealing surface when the door is in its normal closed position, door locking means operative through said door body and clamping means to press said sealing member against said sealing surface witn a force great enough to normally maintain a tight joint between said sealing member and surface, but not great enough to move said sealing member relative to said bearing surface, said sealingmember being arranged relative to said door body for the application to the outer edge of any portion of said sealing member having its inner edge displaced from said sealing surface to thereby momentarily interrupt the normal clamping action holding the inner side of the sealing member in stationary engagement with said bearing surface a distorting force produced by the weight and impact velocity of a body impacting against said outer edge, said sealing member being normally held in sealing engagement with said sealing surface substantially entirely by the frictional contact between the inner side of said sealing member and the adjacent surface of the door.

3. The combination with a coke oven door having an outer metallic door-body with a stiffening rib at its outer side adapted for use in closing a door opening at the end of the horizontal coke oven chamber which has a doorframe with an outwardly facing sealing surface at the margin of said opening, said stiffening rib extending outwardly away from a portion of the door body ad acent the margin of said body of sealing means comprising a rigid frame member formed with an opening receiving said rib means for attaching said frame to said door body, said frame having a peripheral bearing surface which is transverse to said sealing surface when the door is in position to close said door opening, a sealing member in a form of a continuous strip of flexible metal surrounding said bearing surface and having a fiat inner side in engagement with said bearing surface, clamping means carried 'by said member and acting between the latter and said sealing member to normally hold the latter in frictional engagement with said bearing surface and with the inner edge of said sealing member abutting against said sealingsurface and with the outer edge of said sealing member exposed to the local application thereto at substantially any desired point along the length of said outer edge to thereby momentarily interrupt the clamping action applied to an adjacent portion of the outer side of said sealing member and effect contact with said door-frame surface of the portion of the inner edge of said sealing member adjacent the point at which said force is applied a distorting force produced by the weight and impact velocity of a body impacting against said outer edge, said sealing member being normally held in sealing engagement with said sealing surface substantially entirely by the frictional contact between the inner side of said sealing member and the adjacent surface of the door.

4. In maintaining a gas tight seal between an outer metallic door body portion of a coke oven door and the outwardly facing sealing surface of a metallic coke oven door-frame surrounding a door-way into which an inner portion of said door normally extends, by the use of a sealing member in the form of a continuous band of strip metal supported by said door body and having flat inner and outer sides transverse to said sealing surface and havmg an inner sealing edge normally in engagement with said sealing surface, and having said inner side in contact with an abutting bearing surface of said metallic door body portion, the method which consists in applying force to the outer side of said band to normally hold the inner side of said band in fixed frictional engagement with said bearing surface to thereby prevent sliding movement of said band relative to said abutting surface, and applying one or more hammer blows to the outer edge of said sealing member at a point along the length of the said outer edge which is displaced from said sealing surface by a distance greater than the distance between said point and the inner edge of the sealing member, said sealing member being normally held in sealing engagement with said sealing surface substantially entirely by the frictional contact between the inner side of said sealing member and the adjacent surface of the door.

(References on following page) 

1. IN MAINTAINING A GAS TIGHT SEAL BETWEEN AN OUTER METALLIC DOOR-BODY PORTION OF A COKE OVEN DOOR AND THE OUTWARDLY FACING SEALING SURFACE OF A METALLIC COKE OVEN DOOR-FRAME SURROUNDING A DOOR-WAY INTO WHICH AN INNER PORTION OF SAID DOOR NORMALLY EXTENDS, BY THE USE OF A SEALING MEMBER IN THE FORM OF A CONTINUOUS BAND OF STRIP METAL SUPPORTED BY SAID DOOR BODY AND HAVING FLAT INNER AND OUTER SIDES TRANSVERSE TO SAID SEALING SURFACE AND HAVING AN INNER SEALING EDGE NORMALLY IN ENGAGEMENT WITH SAID SEALING SURFACE, AND HAVING SAID INNER SIDE IN CONTACT WITH AN ABUTTING BEARING SURFACE OF SAID METALLIC DOOR BODY PORTION, THE METHOD WHICH CONSISTS IN APPLYING FORCE TO THE OUTER SIDE OF SAID BAND TO NORMALLY HOLD THE INNER SIDE OF SAID BAND IN FIXED FRICTIONAL ENGAGEMENT WITH SAID BEARING SURFACE TO THEREBY PREVENT SLIDING MOVEMENT OF SAID BAND RELATIVE TO SAID ABUTTING SURFACE, AND APPLYING TO THE OUTER EDGE OF SAID SEALING MEMBER AT A POINT ALONG THE LENGTH OF THE SAID OUTER EDGE WHICH IS DISPLACED FROM SAID SEALING SURFACE BY A DISTANCE GREATER THAN THE DISTANCE BETWEEN SAID POINT AND THE INNER EDGE OF THE SEALING MEMBER A DISTORTING FORCE PRODUCED BY THE WEIGHT AND IMPACT VELOCITY OF A BODY IMPACTING AGAINST SAID OUTER EDGE, SAID SEALING MEMBER BEING NORMALLY HELD IN SEALING ENGAGEMENT WITH SAID SEALING SURFACE SUBSTANTIALLY ENTIRELY BY THE FRICTIONAL CONTACT BETWEEN THE INNER SIDE OF SAID SEALING MEMBER AND THE ADJACENT SURFACE OF THE DOOR. 